JP2007149995A - Laminated piezoelectric element and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated piezoelectric element firmly connecting an internal electrode and a side-face electrode. <P>SOLUTION: The laminated piezoelectric element alternately laminates a first electrode layer and a second electrode layer by holding a piezoelectric-body layer. The laminated piezoelectric element contains a plurality of the piezoelectric-body layers 10; the first electrode layer 11a projecting at least a part of an end to the side outer than the adjacent piezoelectric-body layer on the first side face of a laminate, and forming an insulating region 12a between the first electrode layer 11a and the second side face of the laminate; and the second electrode layer 11b projecting at least a part of the end section to the side outer than the adjacent piezoelectric-body layer on the second side face of the laminate, and forming the insulating region 12b between the second electrode layer 11b and the first side face of the laminate. The laminated piezoelectric element further contains a first side-face electrode 13a formed on the first side face of the laminate, connected to at least a part of the end section of the first electrode layer and insulated from the second electrode layer and a second side-face electrode 13b formed on the second side face of the laminate, connected to at least a part of the end of the second electrode layer, and insulated from the first electrode layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a piezoelectric element (laminated piezoelectric element) having a laminated structure used as a piezoelectric actuator, an ultrasonic transducer, and the like, and a method for manufacturing the same.

  A piezoelectric body typified by a material having a lead-based perovskite structure such as PZT (lead zirconate titanate) produces a piezoelectric effect that expands and contracts when a voltage is applied. Piezoelectric elements that utilize such properties are used in various applications such as piezoelectric pumps, piezoelectric actuators, and ultrasonic transducers. The structure of the piezoelectric element is basically a single-layer structure in which electrodes are formed on both sides of one piezoelectric body, but the miniaturization and integration of the piezoelectric element accompanying the recent development of MEMS (micro electro mechanical system) related equipment. As a result, stacked piezoelectric elements in which a plurality of piezoelectric bodies and a plurality of electrodes are alternately stacked are also used.

  FIG. 6 is a cross-sectional view showing the structure of the multilayer piezoelectric element. The piezoelectric element includes a stacked body including alternately stacked piezoelectric layers 100 and internal electrode layers 101 a and 101 b, side electrodes 103 a and 103 b, an upper electrode 104, and a lower electrode 105. Insulating regions 102a and 102b are provided in the internal electrode layers 101a and 101b, respectively.

  The side electrode 103a is connected to the internal electrode layer 101a and insulated from the internal electrode layer 101b by the insulating region 102b. The side electrode 103b is connected to the internal electrode layer 101b and insulated from the internal electrode layer 101a by the insulating region 102a. The upper electrode layer 104 is connected to the side electrode 103a, and the lower electrode layer 105 is connected to the side electrode 103b.

  By forming the electrodes of the piezoelectric elements in this way, the electrodes for applying a voltage to each of the plurality of piezoelectric layers 100 are connected in parallel. As a result, the inter-electrode capacity of the laminated structure as a whole increases, so that an increase in electrical impedance can be suppressed even if the size of the piezoelectric element is reduced.

  Further, instead of providing the insulating regions 102a and 102b in the internal electrode layers 101a and 101b shown in FIG. 1, the internal electrode layer is formed on the entire surface of the piezoelectric layer, and insulated from the end surface of the internal electrode layer on the side surface of the laminate. A laminated piezoelectric element that is insulated from a side electrode by forming a film is also known.

  However, the multilayer piezoelectric element shown in FIG. 6 has a problem that peeling easily occurs in the connection region between the internal electrode layer and the side electrode. The reason is that when the piezoelectric layer expands and contracts, the side electrode cannot follow the displacement of the piezoelectric layer, so that distortion occurs at the interface between the side electrode and the laminate. Further, in a multilayer piezoelectric element in which an insulating film is formed on the side surface of the multilayer body, the insulating film is peeled off from the end face of the internal electrode for the same reason. Therefore, there is a problem that the reliability of the piezoelectric element during operation is low and the lifetime of the element is short.

  Therefore, in view of the above points, a first object of the present invention is to provide a multilayer piezoelectric element in which a side electrode is difficult to peel from an internal electrode layer. A second object of the present invention is to provide a multilayer piezoelectric element in which an insulating film formed on an end face of an internal electrode is difficult to peel off.

  In order to solve the above problems, a multilayer piezoelectric element according to one aspect of the present invention includes a plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer. A multilayer piezoelectric element including a multilayer body in which the at least one first electrode layer and the at least one second electrode layer are alternately stacked with the piezoelectric layer interposed therebetween, wherein a plurality of piezoelectric elements In the first side surface of the multilayer body, at least a part of the end portion projects outward from the adjacent piezoelectric body layer, and the insulating region is between the second side surface of the multilayer body. And at least a part of the end portion of the second side surface of the multilayer body that protrudes outside the adjacent piezoelectric layer, and the multilayer body. An insulating region is provided between the first side surface of the Formed on at least one second electrode layer and the first side surface of the laminate, connected to at least part of the end of the first electrode layer, and insulated from the second electrode layer. Formed on the second side surface of the laminate and connected to at least a part of the end portion of the second electrode layer and insulated from the first electrode layer. A second side electrode.

  A method for manufacturing a multilayer piezoelectric element according to one aspect of the present invention includes a plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer, A method for manufacturing a laminated piezoelectric element comprising a laminate in which at least one first electrode layer and the at least one second electrode layer are alternately laminated with a piezoelectric layer interposed therebetween, wherein the piezoelectric body Forming the first electrode layer so that a first insulating region is provided between the step (a) of forming a layer and the first side surface of the laminate on the piezoelectric layer ( a second insulating region is provided between b), the step (c) of forming a piezoelectric layer on the first electrode layer, and the second side surface of the laminate on the piezoelectric layer. A step (d) of forming a second electrode layer, a step (e) of forming a piezoelectric layer on the second electrode layer, Dicing the laminated body to form the first side surface, thereby causing at least a part of the end portion of the second electrode layer to protrude outward from the adjacent piezoelectric layer; and Dicing the laminate to form the second side surface, thereby causing at least a part of the end portion of the first electrode layer to protrude outward from the adjacent piezoelectric layer; The first side surface of the laminate is connected to at least a part of the end portion of the second electrode layer and insulated from the first electrode layer by the first insulating region. Step (h) of forming an electrode, and connected to at least a part of the end portion of the first electrode layer on the second side surface of the laminate, and from the second electrode layer by the second insulating region And (i) forming a second side electrode so as to be insulated.

  According to the present invention, the internal electrode and the side electrode are connected with a wide contact area by projecting the end portion of the internal electrode outward from the laminated portion of the multilayer body. Thereby, since the connection strength between the internal electrode and the side electrode is improved, even when the piezoelectric layer expands and contracts, the side electrode is difficult to peel from the internal electrode. As a result, it is possible to improve the reliability of the operation of the piezoelectric element and extend the life of the piezoelectric element and the device including the piezoelectric element.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. The same constituent elements are denoted by the same reference numerals, and the description thereof is omitted.
FIG. 1 is a partial cross-sectional perspective view showing the structure of the multilayer piezoelectric element according to the first embodiment of the present invention.
As shown in FIG. 1, the multilayer piezoelectric element according to this embodiment is a columnar structure having, for example, a side of the bottom surface of about 200 μm to 1.0 mm and a height of about 300 μm to 1.0 mm. The multilayer piezoelectric element includes a multilayer body including a plurality of piezoelectric layers 10 and a plurality of internal electrode layers 11a and 11b, and side electrodes 13a and 13b. The plurality of internal electrode layers 11 a and the plurality of internal electrode layers 11 b are alternately stacked with the piezoelectric layer 10 interposed therebetween. In addition, the multilayer piezoelectric element according to this embodiment may further include an upper electrode layer 14 and a lower electrode layer 15.

  The piezoelectric layer 10 has a thickness of about 100 μm, for example, and is formed of a complex oxide having a lead-based perovskite structure such as PZT (lead zirconate titanate). In FIG. 1, five piezoelectric layers 10 are shown, but at least two piezoelectric layers may be provided, and six or more piezoelectric layers may be provided. The piezoelectric layer 10 has a dense and hard structure by being formed by an aerosol deposition method to be described later.

  The internal electrode layers 11a and 11b have a thickness of about 3 μm, for example. The internal electrode layers 11a and 11b are provided with insulating regions 12a and 12b, respectively. In addition, at least a part of the end of the internal electrode layer 11a on the side electrode 13a side and at least a part of the end of the internal electrode layer 11b on the side electrode 13b side protrude outward from the stacked portion of the stacked body. . And as shown in FIG. 1, those protrusion parts are covered with the side electrode so that it may be buried in side electrode 13a and 13b. FIG. 1 shows a state in which the entire end portion of the internal electrode layer 11b on the side electrode 13b side protrudes from the laminated portion.

Such internal electrode layers 11a and 11b may be formed of one type of material or may have a multi-layer structure formed of a plurality of different materials. Examples of the former include metal materials such as platinum (Pt) and alloys (for example, silver palladium). On the other hand, an example of the latter is an electrode having a two-layer structure including an adhesion layer formed of titanium oxide (TiO ₂ ) of about 50 nm and a conductive layer formed of platinum (Pt) of about 3 μm. By providing such an adhesion layer, the adhesion between the conductive layer and the piezoelectric layer 10 can be enhanced.

  The side electrode 13a is connected to the internal electrode layer 11a and insulated from the internal electrode layer 11b by the insulating region 12b. The side electrode 13b is connected to the internal electrode layer 11b and insulated from the internal electrode layer 11a by the insulating region 12a.

  The upper electrode 14 is connected to the side electrode 13a, and the lower electrode 15 is connected to the side electrode 13b. Similar to the internal electrode layers 11a and 11b, these upper electrode 14 and lower electrode 15 may be formed of one kind of material, or may have a multi-layer structure including an adhesion layer and a conductive layer. good.

  A voltage is applied to each piezoelectric layer 10 by supplying a voltage to such a laminated piezoelectric element via the upper electrode 14 and the lower electrode 15. As a result, the multilayer piezoelectric element expands and contracts as a whole due to the piezoelectric effect in each piezoelectric layer 10. Here, the side electrodes 13a and 13b are connected to the internal electrode layers 11a and 11b with a wide contact area at the ends of the internal electrode layers 11a and 11b protruding outward from the laminated portion. Thereby, since the connection strength in those connection parts increases, even when each piezoelectric layer 10 expands and contracts, the side electrodes 13a and 13b can be prevented from peeling from the internal electrode layers 11a and 11b.

Next, a method for manufacturing a multilayer piezoelectric element according to the first embodiment of the present invention will be described with reference to FIGS.
First, as shown in FIG. 2A, the piezoelectric layer 20, the internal electrode layer 21a, the piezoelectric layer 20, and the internal electrode layer 21b are repeatedly formed in this order on the substrate 9. Then, the laminated body 23 is formed.

In the present embodiment, the piezoelectric layer 20 is formed by using an aerosol deposition (AD) method. FIG. 3 is a schematic diagram showing a configuration of a film forming apparatus using the AD method. This film forming apparatus includes an aerosol generating chamber 1, a hoisting gas nozzle 2, a pressure adjusting gas nozzle 3, an aerosol transport pipe 4, a film forming chamber 5, an exhaust pump 6, and an injection disposed in the aerosol generating chamber 1. A nozzle 7 and a substrate holder 8 are included.
The aerosol generation chamber 1 is a container in which raw material powder is placed. The aerosol generation chamber 1 is provided with a container drive unit 1a for agitating the raw material powder disposed therein by applying vibration or the like to the aerosol generation chamber 1.

  A gas cylinder for supplying a carrier gas is connected to the hoisting gas nozzle 2 arranged in the aerosol generating chamber 1. The hoisting gas nozzle 2 generates a cyclone flow by injecting the gas supplied from the gas cylinder into the aerosol generating chamber 1. Thereby, the raw material powder | flour arrange | positioned in the aerosol production | generation chamber 1 is disperse | distributed with gas, and an aerosol is produced | generated.

The pressure adjusting gas nozzle 3 is connected to a gas cylinder that supplies a pressure adjusting gas for adjusting the gas pressure in the aerosol generation chamber 1. By controlling the pressure in the aerosol generation chamber 1 by adjusting the flow rate of the pressure adjusting gas, the speed of the air flow (winding gas) generated in the aerosol generation chamber 1 is controlled.
As the carrier gas and the pressure adjusting gas, nitrogen (N ₂ ), oxygen (O ₂ ), helium (He), argon (Ar), dry air, or the like is used.

The aerosol transport pipe 4 disposed in the aerosol generation chamber 1 transports the aerosol containing the raw material powder wound up in the aerosol generation chamber 1 to the nozzle 7 disposed in the film forming chamber 5.
The inside of the film forming chamber 5 is evacuated by an exhaust pump 6 and thereby maintained at a predetermined degree of vacuum. The injection nozzle 7 disposed in the film forming chamber 5 has an opening of a predetermined shape and size, and the aerosol supplied from the aerosol generation chamber 1 through the aerosol transport pipe 4 is transferred from the opening to the substrate. Inject toward 9 at high speed.

  The substrate holder 8 holds the substrate 9. The substrate holder 8 is provided with a substrate holder driving unit 8a for moving the substrate holder 8 three-dimensionally. As a result, the three-dimensional relative position and relative speed between the spray nozzle 7 and the substrate 9 are controlled. By controlling this relative speed, the thickness of the film formed per round trip can be controlled.

  In such a film forming apparatus, a powder of piezoelectric material as a raw material powder is disposed in the aerosol generating chamber 1 and the substrate 9 is set on the substrate holder 8 and kept at a predetermined film forming temperature. Then, the substrate is moved at a predetermined speed while driving the film forming apparatus to spray aerosol from the spray nozzle 7. As a result, the aerosol (raw material powder) collides with the substrate 9 or the structure deposited on the substrate 9 (referred to as “anchoring”), and the raw material powder is deformed or crushed during the collision. The raw material powder is deposited on the substrate by bonding the particles on the active new surface generated by the above. The film thus formed is firmly in close contact with the underlying layer in the anchor portion (region formed by anchoring) formed in the boundary region with the underlying substrate and internal electrode layer, It has an extremely dense structure due to particle bonding (mechanochemical reaction) on the new surface.

  Here, when the film is formed by the AD method, as the material for the substrate or the internal electrode layer as a base, a material having a hardness that can be deformed or crushed when the raw material powder collides is used. If the hardness of the substrate is insufficient, the raw material powder that collided with the substrate will not be deformed or crushed and will simply bite into the substrate and accumulate, making it impossible to form a dense film by mechanochemical reaction. is there. Therefore, as the substrate 9, for example, a YSZ (yttrium stabilized zirconia) substrate or a SUS substrate is used.

  Referring to FIG. 2 again, the internal electrode layer 21a is formed on the side surface 23a side so as to exceed the dicing line indicated by a broken line, and on the side surface 23b side, the internal electrode layer 21a is formed so as to fit inside the dicing line. Thereby, an insulating region 22a is provided. The internal electrode layer 21b is formed on the side surface 23b side so as to exceed the dicing line indicated by the broken line, and on the side surface 23a side, the internal electrode layer 21b is formed so as to fit inside the dicing line. Thereby, an insulating region 22b is provided.

  As the material of the internal electrode layers 21a and 21b, a material having a certain degree of ductility and hardness is used. The reason why the ductility is required is that, in the present embodiment, by dicing the laminated body 23, the end portions of the internal electrode layers 21a and 21b are protruded from the side surfaces as described later. In addition, as described above, the internal electrode layers 21a and 21b are required to be hard because they serve as base layers when the piezoelectric layer 20 is formed. This is because it is necessary to have sufficient hardness. The characteristics of the material vary somewhat depending on the dicing conditions, etc., but any metal thin film such as platinum (Pt), copper (Cu), nickel (Ni), etc., formed by using a film forming technique such as sputtering or plating. The internal electrodes 21a and 21b can be used. In this embodiment, a platinum thin film formed by sputtering is used.

Next, the laminated body 23 is diced in the dicing line shown in FIG. Thereby, as shown in FIG. 2B, a laminated body 24 is obtained in which the end portions 25 of the internal electrode layers 21a and 21b protrude outward from the laminated portion on the diced side surfaces. The reason why the end portion 25 protrudes in this way is that the internal electrode layers 21 a and 21 b have a hardness higher than that of the piezoelectric layer 20, so that when the laminate 24 is cut, the internal electrode layers 21 a and 21 b have a larger hardness than the piezoelectric layer 20. This is because it tends to remain.
In this step, the substrate 9 may be peeled from the laminate 23.

Next, as shown in FIG. 2C, side electrodes 26 a and 26 b are formed in regions other than the insulating region 27 on the diced side surface of the laminate 24. The insulating region 27 is provided to insulate the side electrodes 26a and 26b from the lower electrode layer 15 and the upper electrode layer 14 (FIG. 1), respectively. The side electrodes 26a and 26b are formed by forming a resist mask in the insulating region 27 and performing sputtering or plating. By using such a film forming method, the side electrodes 26 a and 26 b can be formed so as to cover the protruding end portion 25.
Further, the upper electrode layer 14 and the lower electrode layer 15 shown in FIG. 1 may be formed simultaneously with the side electrodes 26a and 26b, or may be formed after that. Thereby, the multilayer piezoelectric element according to the present embodiment is completed.

A multilayer piezoelectric element according to the present embodiment was manufactured, and an experiment was conducted to peel the side electrode from the multilayer body. As the internal electrode layer, a two-layer structure including a titanium oxide (TiO ₂ ) adhesion layer of about 50 nm and a platinum (Pt) conductive layer of about 3 μm was formed. Moreover, as a dicing condition of the laminated body, a dicing blade NBC-ZS type manufactured by DISCO Corporation was used, and the rotation speed was set to 12000 rpm.

  As a result, the tensile strength of the side electrode was improved about twice as compared with the case where the internal electrode layer was formed by the screen printing method. Note that the screen printing method is a general method for forming electrodes in a conventional multilayer piezoelectric element, and since the formed electrode is soft, the end of the internal electrode layer is laminated even if the laminate is diced. It does not protrude outward from the part.

Next, a laminated piezoelectric element according to the second embodiment of the present invention will be described. FIG. 4 is a partial cross-sectional perspective view showing the structure of the multilayer piezoelectric element according to this embodiment.
Here, in the first embodiment of the present invention, the internal electrode layer is insulated from the side electrode by providing an insulating region, whereas in the second embodiment of the present invention, the internal electrode layer is insulated. It is different in that it is insulated from the side electrode by covering the end of the substrate with an insulating film.

  As shown in FIG. 4, the multilayer piezoelectric element according to this embodiment includes a multilayer body including a plurality of piezoelectric layers 30 and a plurality of internal electrode layers 31a and 31b, and an insulating film 32a formed on a side surface of the multilayer body. And 32b, and side electrodes 33a and 33b. The plurality of internal electrode layers 31 a and the plurality of internal electrode layers 31 b are alternately stacked with the piezoelectric layer 30 interposed therebetween. The multilayer piezoelectric element according to the present embodiment may further include an upper electrode layer 34 and a lower electrode layer 35.

The internal electrode layers 31 a and 31 b are formed on the entire surface of the piezoelectric layer 30. In addition, at least a part of the end portions of the internal electrode layers 31a and 31b on the side surface electrodes 33a and 33b side protrudes outward from the laminated portion. FIG. 4 shows a state in which the entire end portions on the side electrode 33b side of the internal electrode layers 31a and 31b protrude from the laminated portion.
On the side electrode 33a side, the end of the internal electrode layer 31a is covered so as to be buried in the side electrode 33a. In addition, on the same side surface, an insulating film 32b is formed so as to cover the end portion of the internal electrode layer 31b. Similarly, on the side electrode 33b side, the end of the internal electrode layer 31b is covered with the side electrode 33b, and an insulating film 32a is formed so as to cover the end of the internal electrode layer 31a.
By forming the insulating films 31a and 31b in this manner, the side electrode 33a is connected to the internal electrode layer 31a and insulated from the internal electrode layer 31b. On the other hand, the side electrode 33b is connected to the internal electrode layer 31b and insulated from the internal electrode layer 31a.

  In the present embodiment, since the insulating films 32a and 32b are respectively formed at the end portions of the internal electrode layers 31a and 31b protruding outward from the laminated portion, the contact area between both is widened. As a result, since the connection strength between the two increases, even when the piezoelectric layer 30 expands and contracts by driving the piezoelectric element, the insulating films 32a and 32b are prevented from being separated from the internal electrode layers 31a and 31b. Can do. Also, the side electrodes 33a and 33b can be prevented from being peeled off by connecting to the internal electrode layers 31a and 31b at the protruding ends.

Next, a method for manufacturing a multilayer piezoelectric element according to the second embodiment of the present invention will be described with reference to FIG.
First, as illustrated in FIG. 5A, the stacked body 42 is formed by alternately stacking the piezoelectric layers 40 and the internal electrode layers 41 on the substrate 9. The piezoelectric layer 40 is formed by the AD method as in the first embodiment. The internal electrode layer 41 is formed by sputtering or plating using the same material as that described in the first embodiment.

  Next, the laminated body 42 is diced along a dicing line indicated by a broken line in FIG. Thereby, as shown to (b) of FIG. 5, the molded laminated body 43 is obtained. An end portion 44 of the internal electrode layer 41 protruding outward from the laminated portion is formed on the diced side surface of the laminated body 43. In this step, the substrate 9 may be peeled from the stacked body 42.

  Next, as shown in FIG. 5C, every other insulating film 45 a is formed on the end 44 of the internal electrode layer 41 on the diced side surface 43 a of the multilayer body 42. In addition, on the other diced side surface 43b, the insulating film 45b is formed on the end portion 44 of the internal electrode layer 41 so as to alternate with the insulating film 45a. These insulating films 45a and 45b are formed by, for example, attaching glass powder having a softening point of about 500 ° C. to 700 ° C. to the end portion 44 by electrophoresis (electrodeposition method) or screening paste containing glass powder. It is formed by forming a film on the end portion 44 by a printing method. Alternatively, an aerosol deposition method in which a film is formed by spraying an aerosol in which powder of an insulating material is dispersed on the end 44 of the internal electrode layer 41 may be used.

  Next, as shown in FIG. 5D, side electrodes 46a and 46b are formed in a region other than the insulating region 47 on the diced side surface of the laminate 43 by sputtering or plating. Furthermore, the upper electrode layer 34 and the lower electrode layer 35 shown in FIG. 4 may be formed. Thereby, the multilayer piezoelectric element according to the present embodiment is completed.

  The multilayer piezoelectric element according to the first and second embodiments of the present invention described above is used as a piezoelectric pump, a piezoelectric actuator, an ultrasonic transducer that transmits and receives ultrasonic waves in an ultrasonic probe, and the like. In that case, the laminated piezoelectric element can be used alone or can be used as a piezoelectric element array by arranging the laminated piezoelectric elements in one or two dimensions.

  The present invention can be used in a laminated piezoelectric element used as a piezoelectric actuator, an ultrasonic transducer, and the like and a manufacturing method thereof.

1 is a partial cross-sectional perspective view showing the structure of a multilayer piezoelectric element according to a first embodiment of the present invention. It is a figure for demonstrating the manufacturing method of the lamination type piezoelectric element which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the structure of the film-forming apparatus using the aerosol deposition method. It is a partial cross section perspective view which shows the structure of the lamination type piezoelectric element which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the lamination type piezoelectric element which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the structure of the conventional lamination type piezoelectric element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Aerosol production | generation chamber 2 Hoisting gas nozzle 3 Pressure regulation gas nozzle 4 Aerosol conveyance pipe 5 Deposition chamber 6 Exhaust pump 7 Injection nozzle 8 Substrate holder 9 Substrate 10, 20, 30, 40, 100 Piezoelectric layer 11a, 11b, 21a, 21b, 31a, 31b, 41,
101a, 101b Internal electrode layers 12a, 12b, 22a, 22b, 27, 47, 102a, 102b Insulating regions 13a, 13b, 26a, 26b, 33a, 33b, 46a, 46b,
103a, 103b Side electrodes 14, 34, 103 Upper electrode layers 15, 35, 105 Lower electrode layers 23, 24, 42, 43 Laminated bodies 24a, 24b, 43a, 43b Side surfaces 25, 44 Ends 32a, 32b, 45a, 45b Insulation film

Claims (14)

A plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer, the at least one first electrode layer and the at least one second electrode layer; Is a stacked piezoelectric element including a stacked body that is alternately stacked with a piezoelectric layer interposed therebetween,
A plurality of piezoelectric layers;
In the first side surface of the multilayer body, at least a part of the end portion protrudes outside the adjacent piezoelectric layer, and an insulating region is provided between the second side surface of the multilayer body. At least one first electrode layer comprising:
In the second side surface of the multilayer body, at least a part of the end portion protrudes outside the adjacent piezoelectric layer, and an insulating region is provided between the first side surface of the multilayer body. At least one second electrode layer,
A first side electrode formed on the first side surface of the laminate, connected to at least a part of the end of the first electrode layer, and insulated from the second electrode layer; ,
A second side surface electrode formed on the second side surface of the laminate, connected to at least a part of the end portion of the second electrode layer, and insulated from the first electrode layer; ,
A laminated piezoelectric element comprising: A plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer, the at least one first electrode layer and the at least one second electrode layer; Is a stacked piezoelectric element including a stacked body that is alternately stacked with a piezoelectric layer interposed therebetween,
A plurality of piezoelectric layers;
In at least two side surfaces of the laminate, at least one first electrode layer in which at least a part of the end protrudes outside the adjacent piezoelectric layer; and
A first insulating film covering the end portion of the first electrode layer on a first side surface of the two side surfaces of the stacked body;
In the two side surfaces of the multilayer body, at least one second electrode layer in which at least a part of the end portion projects outward from the adjacent piezoelectric layer; and
A second insulating film covering the end portion of the second electrode layer on a second side surface of the two side surfaces of the stacked body;
Formed on the first side surface of the laminate, insulated from the first electrode layer by the first insulating film, and connected to at least a part of the end of the second electrode layer A first side electrode,
Formed on the second side surface of the stacked body, insulated from the second electrode layer by the second insulating film, and connected to at least a part of the end of the first electrode layer; A second side electrode,
A laminated piezoelectric element comprising:   The plurality of piezoelectric layers are formed by an aerosol deposition method in which a piezoelectric material is deposited by spraying a powder of piezoelectric material toward a substrate or the at least one first or second electrode layer. Item 3. The laminated piezoelectric element according to Item 1 or 2.   The multilayer piezoelectric element according to claim 1, wherein the at least one first and second electrode layers are formed by a sputtering method or a plating method.   5. The method according to claim 1, wherein each of the at least one first and second electrode layers includes a conductive layer and an adhesion layer formed between the conductive layer and the piezoelectric layer. The laminated piezoelectric element described. A plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer, the at least one first electrode layer and the at least one second electrode layer; Is a method for manufacturing a stacked piezoelectric element including a stacked body that is alternately stacked with piezoelectric layers interposed therebetween,
Forming a piezoelectric layer (a);
A step (b) of forming a first electrode layer on the piezoelectric layer so that a first insulating region is provided between the first side surface of the multilayer body; and
Forming a piezoelectric layer on the first electrode layer (c);
A step (d) of forming a second electrode layer on the piezoelectric layer so that a second insulating region is provided between the second side surface of the multilayer body; and
Forming a piezoelectric layer on the second electrode layer (e);
(F) projecting at least a part of the end portion of the second electrode layer to the outside of the adjacent piezoelectric layer by dicing the formed laminate to form the first side surface; ,
Dicing the laminated body to form a second side surface, thereby causing at least a part of the end of the first electrode layer to protrude outward from the adjacent piezoelectric layer;
The first side surface of the laminate is connected to at least a part of the end portion of the second electrode layer, and is insulated from the first electrode layer by the first insulating region. Forming a first side electrode (h);
The second side surface of the laminate is connected to at least a part of the end portion of the first electrode layer, and is insulated from the second electrode layer by the second insulating region. Forming a second side electrode (i);
A method for manufacturing a laminated piezoelectric element comprising:   Each of the steps (a), (c) and (e) uses an aerosol deposition method in which a piezoelectric material is deposited by spraying a powder of the piezoelectric material toward the substrate or the first or second electrode layer. The method for manufacturing a multilayer piezoelectric element according to claim 6, further comprising forming the piezoelectric layer.   8. The multilayer piezoelectric element according to claim 6, wherein each of the steps (b) and (d) includes forming the first or second electrode layer by using a sputtering method or a plating method. Method.   Each of the steps (b) and (d) includes forming the first or second electrode layer by disposing a conductive layer on the piezoelectric layer via an adhesion layer. The manufacturing method of the lamination type piezoelectric element of any one of -8. A plurality of piezoelectric layers, at least one first electrode layer, and at least one second electrode layer, the at least one first electrode layer and the at least one second electrode layer; Is a method for manufacturing a stacked piezoelectric element including a stacked body that is alternately stacked with piezoelectric layers interposed therebetween,
A step (a) of forming a laminate by laminating the piezoelectric layer and the first and second electrode layers;
Dicing the formed laminate to form the first side surface, thereby causing at least part of the end portions of the first and second electrode layers to protrude outward from the adjacent piezoelectric layers ( b) and
(C) projecting at least a part of the end portions of the first and second electrode layers beyond the adjacent piezoelectric layers by forming the second side surface by dicing the laminate. When,
A step (d) of forming a first insulating film so as to cover an end of the first electrode layer on the first side surface of the multilayer body;
A step (e) of forming a second insulating film so as to cover an end of the second electrode layer on the second side surface of the multilayer body;
The first side surface of the stacked body is insulated from the first electrode layer by the first insulating film and is connected to at least a part of the end portion of the second electrode layer. Forming a first side electrode (f);
The second side surface of the stacked body is insulated from the second electrode layer by the second insulating film and is connected to at least a part of the end portion of the first electrode layer. Forming a second side electrode (g);
A method for manufacturing a laminated piezoelectric element comprising:   Step (a) forms the piezoelectric layer by using an aerosol deposition method in which a piezoelectric material is deposited by spraying a powder of the piezoelectric material toward a substrate or the first or second electrode layer. The manufacturing method of the lamination type piezoelectric element of Claim 10 containing these.   The method of manufacturing a multilayer piezoelectric element according to claim 10 or 11, wherein step (a) includes forming the first and second electrode layers by using a sputtering method or a plating method.   The process (a) includes forming the first and second electrode layers by disposing a conductive layer on the piezoelectric layer via an adhesion layer, 13. A method for producing a laminated piezoelectric element according to the item. In each of the steps (d) and (e), an aerosol deposition method in which an insulating material is deposited by spraying a powder of an insulating material toward the end of the first or second electrode layer, or electrodeposition The method for manufacturing a multilayer piezoelectric element according to claim 10, comprising forming the first and second insulating films by using a method.

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